Sweeping machine for working ground surfaces, in particular lawns

ABSTRACT

A sweeping machine for working ground surfaces, in particular lawns comprises a machine frame adapted to be moved in the traveling direction, at least one wheel axle with at least one wheel, said wheel axle being supported in the machine frame transversely to the traveling direction, said wheel axle supporting the machine frame parallel to the ground surface, a least one sweeping element adapted to be driven for rotation about a sweeping element axis, said sweeping element axis extending substantially parallel to the ground surface, and said sweeping element is in contact with the ground surface when in an operating position. The sweeping machine of the invention provides that the sweeping element axis of the at least one sweeping element is adapted to be moved from a first operating position, assumed when travelling straight, to a second operating position, assumed when driving a curve, in which second position the sweeping element axis is in a position pivoted towards the inner side of the curve.

This application is a continuation of and claims priority from U.S.patent application Ser. No. 13/750,447, filed on Jan. 25, 2013, entitled“SWEEPING MACHINE FOR WORKING GROUND SURFACES, IN PARTICULAR LAWNS,” nowissued as U.S. Pat. No. 9,351,446 B2, and which in turn claims priorityunder 35 U.S.C. § 119 to German Patent Application No. 20 2012 010494.2, filed Nov. 5, 2012, the entire contents of which are herebyincorporated by reference.

The invention refers to a sweeping machine for working ground surfaces.

Sweeping machines for working ground surfaces are known that comprise amachine frame adapted to be moved in the traveling direction, in whichmachine frame at least one wheel axle with at least one wheel issupported transversely to the traveling direction, the wheel axlecarrying the machine frame parallel to the ground surface. The sweepingmachine has at least one sweeping element adapted to be rotated about asweeping element axis, with the sweeping element axis extending parallelto the ground surface and the sweeping element being in contact with theground surface when in an operating position.

However, these sweeping machines have a drawback in that, in particularwhen driving curves, the sweepings such as leaves or sand aretransported towards the outer edge of the curve and are transported outfrom the sweeping machine at the outer edge of the curve. Further, thereis a need to provide sweeping machines that can be manufactured aseconomically as possible and as simply as possible, which sweepers canbe transported to the site to be swept in a transport position in whichthe sweeping element does not touch the ground surface, and wherein thesweeping element is driven only when it is in contact with the groundsurface.

It is thus an object of the present invention to provide a sweepingmachine configured such that the material to be swept is not transportedout from the sweeping machine even when driving a curve.

It is another object of the present invention to provide a sweepingmachine that is economic and simple to manufacture, the sweeping elementof the sweeping machine being driven only when in contact with theground.

The invention advantageously provides that the sweeping element axis ofthe at least one sweeping element is adapted to be shifted from a firstoperating position, assumed when traveling in a straight direction, to asecond operating position, assumed when driving curves, the sweepingelement axis in the second position being pivoted towards the inner sideof the curve with respect to the first operating position.

This is advantageous in that the material to be swept is prevented frombeing transported towards the outer side of the curve, e.g. bycentrifugal forces, and from being transported out from the sweepingmachine.

The sweeping element axis may be pivotable from the first operatingposition to the second operating position about a substantially verticalpivot axis.

The sweeping element may be a brush roller, preferably a round brushroller.

The vertical pivot axis may extend through a bearing at one of the freeends of the sweeping element axis.

A single wheel axle may be provided that is supported in the machineframe.

The at least one wheel axle may drive the at least one sweeping elementand/or a transmission.

The machine frame may comprise a coupling device for a towing vehicle.

At least two sweeping elements may be provided, with one sweepingelement preferably being arranged ahead of the wheel axle, seen in thedirection of travel, and one sweeping element being arranged behind thewheel axle, seen in the traveling direction.

In the first operating position, the sweeping element axis of the atleast one sweeping element may be arranged in parallel with the at leastone wheel axle.

In the second operating position, the sweeping element axis ispreferably no arranged in parallel with the wheel axle.

The sweeping element axis of the at least one sweeping element may bepivotable substantially in a plane parallel to the ground surface.

The sweeping element axis of the at least one sweeping element maycomprise a first and a second end, at least one end being adjustablewith respect to the machine frame by means of an adjusting means inorder to pivot the sweeping element axis.

The adjusting means may be manually and/or pneumatically and/orhydraulically actuatable.

When driving curves, the outer end of the at least one sweeping elementmay be pivotable in a forward direction with respect to the frame, seenin the traveling direction, and/or the end on the inner side of thecurve of the at least one sweeping element may be adjustable in arearward direction with respect to the frame.

The adjusting means for the at least one sweeping element axis may becontrollable in an automatic manner depending on the steering angle ofthe towing vehicle or on a curve travel detector signal from a detectorprovided on the machine frame.

The at least one sweeping element axis may be supported in an innerframe element of the machine frame, which is vertically adjustable withrespect to the machine frame such that the sweeping element can be movedto a transport position in which the sweeping element is not in contactwith the ground surface.

The inner frame element may be pivotable with respect to the machineframe about an axis parallel to the wheel axle or about the wheel axle.

In the operating position, the at least one sweeping element may bedrivingly coupled with the wheel axle via a transmission, in particulara belt drive or a chain drive, while in the transport position, thesweeping element may be adapted to be uncoupled from the wheel axle bymeans of a clutch, for example.

The invention further advantageously provides a method for sweepingground surfaces, in particular lawns, wherein a vehicle moves a sweepingmachine in the traveling direction, wherein the sweeping machine issupported by at least one wheel on a wheel axle of the sweeping machinethat extends transversely to the traveling direction, and wherein theground surface is swept with at least one sweeping element extendingsubstantially parallel to the wheel axle and driven to rotate about asweeping element axis. The sweeping element is pivoted from a firstoperating position for straight travel, in which position the sweepingelement axis of the sweeping element is in a substantially orthogonalposition with respect to the traveling direction, to a second positionfor traveling curves, in which the sweeping element axis of the sweepingelement is moved into a position pivoted towards the inner side of thecurve.

The present invention provides a sweeping machine, wherein, in theoperating position, the sweeping element is in contact with the groundand sweeps the same, wherein, in the operating position, the sweepingelement axis is coupled with the wheel axle so that the sweeping elementcan be driven by rotation of the wheel axle, wherein the sweepingelement is adapted to be pivoted to a transport position in which thesweeping element does not contact the ground, wherein, in the transportposition, the wheel axle and the sweeping element axis are decoupledfrom each other so that the sweeping element is not driven while in thetransport position.

By pivoting the sweeping element from the operating position to thetransport position, the wheel axle and the sweeping element axis can bedecoupled from each other.

By pivoting the sweeping element from the transport position to theoperating position, the wheel axle and the sweeping element axis can becoupled with each other.

The wheel axle and the sweeping element axis may be adapted to becoupled via a transmission, in particular via a belt drive or a chaindrive.

A clutch may be provided that decouples the wheel axle from the sweepingelement axis.

The clutch may be actuated using a cable pull when pivoting the sweepingelement from the operating position to the transport position and viceversa.

Further, the present invention may provide another method for sweepingground surfaces, in particular lawns, wherein a vehicle moves a sweepingmachine in the traveling direction, wherein the sweeping machine issupported by at least one wheel on a wheel axle of the sweeping machinethat extends transversely to the traveling direction, and wherein theground surface is swept with at least one sweeping element extendingsubstantially parallel to the wheel axle and driven to rotate about asweeping element axis, and wherein, in an operating position in whichthe sweeping element is in contact with the ground, the sweeping elementaxis is coupled with the wheel axle and is driven by rotation of thewheel axle. In this method it may advantageously be provided that thesweeping element is pivoted from an operating position to a transportposition in which the sweeping element does not contact the ground,wherein the pivoting to the transport position causes the wheel axle andthe sweeping element axis to become decoupled from each other so thatthe sweeping element is not driven in the transport position.

When pivoting the sweeping element from the transport position to anoperating position, the pivoting causes the wheel axle and the sweepingelement axis to be coupled.

A sweeping machine or a method of sweeping a ground surface may includethe features as described in the description.

The following is a detailed description of an embodiment of theinvention with reference to the drawings.

The Figures schematically show:

FIG. 1 a sweeping machine in side elevational view,

FIG. 2 the sweeping machine of FIG. 1 in the transport position,

FIG. 3 a top plan view on the sweeping machine,

FIG. 4 the sweeping machine in the second operating position,

FIG. 5 the machine frame of the sweeping machine,

FIG. 6 the machine frame of the sweeping machine in the transportposition,

FIG. 7 a hydraulic adjusting means for pivoting the sweeping elementfrom the first to the second operating position,

FIG. 8 an electric adjusting means,

FIG. 9 a manual adjusting means.

FIG. 1 illustrates a sweeping machine 1 for working a ground surface 40.The sweeping machine 1 can be pulled in the traveling direction 42 usinga towing vehicle not illustrated herein. A coupling device 22 isprovided for the towing vehicle.

The sweeping machine illustrated comprises a machine frame 2 adapted tobe moved in the traveling direction 42 by means of the towing vehicle. Awheel axle 10 with two wheels 4 is supported in the machine frame 2. Thewheel axle 10 extends substantially parallel to the ground surface 40.The wheel axle 10 supports the machine frame 2 substantially parallel tothe ground surface 40. When the sweeping machine is moved in thetraveling direction 42, the wheels 4 are rotated. The rotation of thewheels 4 drives the wheel axle 10.

The sweeping machine preferably comprises two sweeping elements 6, 8adapted to be rotated about a respective sweeping element axis 12, 14.The sweeping elements 6, 8 are brush rollers. The sweeping element axes12, 14 substantially extend parallel to the ground surface 40. In FIG.1, the sweeping elements are illustrated in an operating position inwhich the sweeping elements are in contact with the ground surface 40and sweep the ground surface 40. The sweeping elements 6, 8 preferablyrotate in a direction opposite to the rotation of the wheels 4.Alternatively, the sweeping elements 6, 8 may also rotate in the samedirection as the wheels 4.

In the operating position, the sweeping element axes 12 and 14 arecoupled with the wheel axle 10. This is illustrated in FIG. 3. In thecase illustrated, the coupling may be effected through transmissions 13,preferably chain drives or belt drives. In the embodiment illustrated,the transmissions 13 are chain drives. The sweeping element axes 12, 14,and thus the sweeping elements 6 and 8, can be driven by the rotation ofthe wheel axle 10 and the wheels 4.

Using a piston/cylinder element 16, the sweeping elements 6 and 8 can bepivoted to a transport position. FIG. 2 illustrates the sweepingelements 6 and 8 in the transport position. In the transport positionthe sweeping elements 6 and 8 do not contact the ground surface 40, andthe wheel axle 10 and the sweeping element axes 12 and 14 are decoupledfrom each other in the transport position so that the sweeping elements6 and 8 are not driven in the transport position. Pivoting the sweepingelements 6, 8 from the operating position to the transport positioncauses the wheel axle 10 and the sweeping element axes 12, 14 to bedecoupled from each other. This is achieved by means of the clutch 18.

The pivoting from the operating position to the transport position andthe decoupling will be described with reference to FIGS. 5 and 6. FIGS.5 and 6 show only a part of the machine frame 2. The machine frame 2comprises inner frame elements 36, 38. The sweeping elements 6, 8 arerespectively supported on either side in one of the inner frame elements36, 38 by the sweeping element axes 12, 14. The inner frame elements 36,38 are arranged at both ends of the sweeping element axes 12, 14. Theinner frame elements 36, 38 may be pivoted about a pivot axis extendingparallel to the wheel axle or about the wheel axle 10.

When pivoting the inner frame elements 36, 38, a cable pull element 43can be actuated as in the embodiment illustrated, which cable pullelement actuates the clutch 18 and disengages the wheel axle 10 from thesweeping element axes 12, 14. Upon pivoting from the operating positionto the transport position, i.e. upon pivoting upward, the wheel axle 10is disengaged from the sweeping element axes 12, 14 via the clutch 18.Upon pivoting from the transport position to the operating position,i.e. upon pivoting downward, the wheel axle 10 is again coupled with thesweeping element axes 12, 14. This means that the sweeping elements 6, 8are not driven in the transport position, whereas in the operatingposition, in which the sweeping elements 6, 8 sweep the ground surface40, they are driven by the wheel axle 10.

FIG. 3 illustrates the sweeping machine 1 in top plan view. In FIG. 3the sweeping machine is shown in a first operating position. In thisfirst operating position the sweeping element axes 12 and 14 arearranged parallel to the wheel axle 10 and, when traveling straight,they are arranged orthogonally to the travelling direction 42.

When driving a curve, the sweeping element axes 12, 14 of the sweepingelements 6, 8 can be moved to a second operating position in which theyassume a position pivoted towards the inner side of the curve. Thesecond operating position is illustrated in FIG. 4. The sweeping elementaxes 12, 14 have been moved to a position pivoted towards the inner sideof the curve. The direction of curve travel is indicated by thereference numeral 24. The sweeping element axes are preferably pivotedaround a substantially vertical pivot axis from the first operatingposition to the second operating position.

The sweeping element axes 12, 14 each have a first end 44, 46 and arespective second end 48, 50, which are supported in the inner frameelements 36, 38 of the machine frame 2. The fact that the sweepingelement axes 12, 14 are pivoted towards the inner side of the curvemeans that the sweeping elements 6, 8 are turned more in the directionof the curve. In other words, the end at outer side of the curve ispivoted forward with respect to the traveling direction and/or the endat the inner side of the curve is pivoted rearward with respect to thetraveling direction.

In order to pivot the sweeping element axes 12, 14, the sweeping elementaxes 12, 14 of the sweeping elements 6, 8 may be adjustable at the firstend 44, 46 and/or at a second end 48, 50 relative to the machine frame 2by means of an adjusting means. In the embodiment illustrated thesweeping element axes 12, 14 are adjusted in the inner frame elements36, 38 at the respective second end 48, 50 relative to the machine frame2 so that the sweeping elements 6, 8 are pivoted about a pivot axis 26,28 respectively extending in the first end 44, 46. The pivot axes 26, 28preferably extend substantially vertically, i.e. substantiallyorthogonally to the ground surface 40.

FIGS. 7 to 9 illustrate different adjusting means 52, 54, 56 forpivoting the sweeping element axes 12, 14. FIG. 7 illustrates ahydraulic adjusting means 52. FIG. 8 illustrates an electric adjustingmeans and FIG. 9 illustrates a manual adjusting means.

The sweeping elements 6 and 8 can be moved from the first operatingposition to the second operating position when driving a curve. As analternative, the sweeping elements 6, 8 may also be moved from the firstoperating position to the transport position first. Thereafter, theadjusting means 52, 54, 56 can be actuated and the sweeping element axes12, 14 can be adjusted with respect to frame elements 36, 38 of themachine frame 2. The sweeping elements 6, 8 may then be lowered to theoperating position again, the adjustment of the sweeping element axes12, 14 causes the sweeping elements 6, 8 to be moved to the secondoperating position as they are lowered, with the sweeping elements 6,8assuming a position pivoted to the inner side of the curve.

The adjusting means 52, 54, 56 for the at least one sweeping elementaxis 12, 14, may be controllable in an automatic manner depending on thesteering angle of the towing vehicle or on a curve travel detectorsignal from a detector 100 provided on the machine frame 2.

The invention claimed is:
 1. A sweeping machine for working groundsurfaces, comprising: a machine frame adapted to be moved in a travelingdirection, at least one wheel axle with at least one wheel, said wheelaxle being supported in the machine frame transversely to the travelingdirection, said wheel axle supporting the machine frame parallel to theground surface, at least one sweeping element adapted to be driven forrotation about a sweeping element axis, said sweeping element axisextending substantially parallel to the ground surface, and saidsweeping element is in contact with the ground surface when in anoperating position, wherein the sweeping element axis of the at leastone sweeping element is adapted to be moved from a first operatingposition, assumed when travelling straight, to a second operatingposition, assumed when driving a curve, in which second position thesweeping element axis is in a position pivoted towards the inner side ofthe curve, wherein the sweeping element axis of the at least onesweeping element has a first and a second supported end, at least oneend being adjustable with respect to the machine frame by means of anadjusting means in order to pivot the sweeping element axis, wherein theadjusting means is adapted to be actuated, pneumatically orhydraulically, wherein the adjusting means for the at least one sweepingelement axis is configured to be automatically adjusted based on thesteering angle of a towing vehicle or on a curve travel detector signalfrom a detector provided on the machine frame.
 2. The sweeping machineaccording to claim 1, wherein the sweeping element is a brush roller. 3.The sweeping machine according to claim 1, wherein a single wheel axleis provided which is supported in the machine frame.
 4. The sweepingmachine according to claim 1, wherein the at least one wheel axle drivessaid at least one sweeping element or a transmission.
 5. The sweepingmachine according to claim 1, wherein in the first operating position,the sweeping element axis of the at least one sweeping element isarranged parallel to the at least one wheel axle.
 6. The sweepingmachine according to claim 1, wherein the sweeping element axis ispivotable from the first operating position to the second operatingposition about a substantially vertical pivot axis.
 7. The sweepingmachine according to claim 6, wherein the vertical pivot axis extendsthrough a bearing on at least one free end of the sweeping element axis.8. The sweeping machine according to claim 1, wherein the sweepingelement axis of the at least one sweeping element is pivotablesubstantially in a plane parallel to the ground surface.
 9. The sweepingmachine according to claim 1, wherein when driving a curve, the end ofthe at least one sweeping element, situated on the outer side of thecurve, is adapted to be adjusted forward with respect to the frame, seenin the traveling direction, the end of the at least one sweepingelement, situated on the inner side of the curve, is adapted to beadjusted rearward with respect to the frame.
 10. The sweeping machineaccording to claim 1, wherein the at least one sweeping element axis issupported in an inner frame element of the machine frame, which isvertically adjustable with respect to the machine frame such that thesweeping element can be moved to a transport position in which thesweeping element is not in contact with the ground surface.
 11. Thesweeping machine according to claim 1, wherein in the first and secondoperating position, the at least one sweeping element is drivinglycoupled with the wheel axle via a transmission, while in a transportposition, the sweeping element is adapted to be uncoupled from the wheelaxle by means of a clutch.
 12. A sweeping machine adapted to be pulledby a towing vehicle, for sweeping a ground, comprising: a machine frame,at least two wheels adapted to rotate about at least one wheel axle, atleast one sweeping element adapted to rotate about a sweeping elementaxis, the sweeping element being in contact with the ground, when in itsoperating position, and sweeps the ground, the sweeping element axis inthe operating position being coupled with the wheel axle so that thesweeping element can be driven by the rotation of the wheel axle,wherein the sweeping element is adapted to be pivoted to a transportposition in which the sweeping element does not contact the ground, thewheel axle and the sweeping element axis being decoupled from each otherin the transport position so that the sweeping element is not driven inthe transport position, wherein the sweeping element axis of the atleast one sweeping element has a first and a second supported end, atleast one end being adjustable with respect to the machine frame bymeans of an adjusting means in order to pivot the sweeping element axis,wherein the adjusting means is adapted to be actuated, pneumatically orhydraulically, wherein the adjusting means for the at least one sweepingelement axis is further configured to be automatically adjusted based onthe steering angle of a towing vehicle or on a curve travel detectorsignal from a detector provided on the machine frame.
 13. The sweepingmachine according to claim 12, wherein the wheel axle and the sweepingelement axis are adapted to be decoupled from each other by pivoting thesweeping element from the operating position to the transport position.14. The sweeping machine according to claim 12, wherein the wheel axleand the sweeping element axis are adapted to be coupled with each otherby pivoting the sweeping element from the transport position to theoperating position.
 15. The sweeping machine according to claim 12,wherein the wheel axle and the sweeping element axis are adapted to becoupled via a transmission.
 16. The sweeping machine according to claim12, wherein a clutch is provided that decouples the wheel axle from thesweeping element axis.